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Fuel Injectors --, Checking

General Description 

The Fuel Injectors -- are controlled by the Engine Control Module -J623- and are mounted normally in the cylinder head. The fuel injectors spray high-pressure atomized fuel directly into the combustion chamber.

Special tools and workshop equipment required 

Test requirements 

Test Procedure 

NOTE:

Note the CA1 and CMC both use the ECM connector T105a, and the CA2 uses the ECM connector T105b. Both connectors are identical except for the suffix of "a" or "b". For simplicity, please use the suffix "a".

Step Procedure Result / Action to Take
1
  • PERFORM: Preliminary Check to verify the customers complaint. Refer to .
-- Was Complaint verified?
-- YES: -- NO:
  • GATHER more information from customer about the complaint.
  • IGNITION: OFF.
  • DISCONNECT: Harness connector from suspect Fuel Injector --.
  • CHECK: Suspect Fuel Injector -- component connector terminals 1 to 2 for resistance (refer to appropriate wiring diagram for correct terminal and connector locations).
  • SPECIFIED VALUE: 0.5 - 15 Ω (@ approx. 20° C).
-- Was Value obtained?
-- YES: -- NO:
  • REMOVE: Engine Control Module - J623-. Refer to appropriate Service Information.
  • CHECK: Suspect Fuel Injector -- harness connector terminal 1 to the Engine Control Module - J623- harness connector T105a / xx for resistance (refer to appropriate wiring diagram for correct terminal and connector locations).
  • CHECK: Suspect Fuel Injector -- harness connector terminal 2 to the Engine Control Module - J623- harness connector T105a / xx for resistance (refer to appropriate wiring diagram for correct terminal and connector locations).
  • SPECIFIED VALUE: 0.5 Ω (± 0.3 Ω).
-- Were Values obtained?
-- YES:
  • TIP: The Fuel Injector -- may fail under loaded operation; please swap a known good Fuel Injector -- prior to continuing to the next step.
  • GO TO: Step 4 Fuel Injectors --, CHECKING - 4 .
-- NO:
  • PERFORM: Visual Inspection of wiring and component.
  • CHECK: Wiring for open, high resistance, short or harness connector for damage, corrosion, loose or broken terminals.
  • REPAIR: Faulty wiring or connector.
  • GO TO: Step 4 Fuel Injectors --, CHECKING - 4 .
  • Final Procedure 
  • Perform a road test to verify repair.
-- Does the original DTC return?
-- YES:
  • CHECK: Engine Control Module -J623- harness connector for any damaged, pushed-out pins.
  • REPAIR: As necessary.
  • If all electrical connections are OK:
  • REPLACE: Engine Control Module -J623-. Refer to appropriate Service Information.
  • Clear the DTC's. Refer to .
  • Repair is complete. Generate Readiness Code. Refer to .
  • Return vehicle to Customer.
-- NO:
  • Perform the diagnostic procedure for any DTC's.
  • If no DTC's return, the repair is complete.
  • Return vehicle to customer.